Postback Tracking Guide for Affiliates: How Server-to-Server Works

February 6, 2026

Sara Bregasi

Sara Bregasi

Content Writer

Postback tracking is a reliable method of server-to-server (S2S) conversion tracking that gives affiliate marketers accurate performance data without relying on browser cookies or pixels

Unlike traditional tracking methods that can fail when cookies are blocked or scripts don’t fire, postback tracking sends conversions directly from one server to another. This process ensures that every lead, sale or signup is properly attributed. With the ongoing privacy regulations, this method helps affiliates scale their campaigns with confidence. 

In this guide, we’ll break down how postback tracking works and how to implement it effectively for your affiliate marketing campaigns.

What Is Postback Tracking in Affiliate Marketing?

Postback tracking is a server-to-server tracking method, commonly used in affiliate marketing to record conversions events (e.g., sales, leads) by passing data directly between the affiliate network’s and the tracking platform’s server. 

As mentioned in the introduction, this backend tracking method is not reliant on cookies or browser limitations, making it more accurate. 

In affiliate marketing, postback tracking is especially important because it ties each conversion back to the correct click and affiliate partner. 

Key Terms You Need to Know

  • Click ID: Unique identifier generated when a user clicks on an affiliate link. When a conversion happens, this click ID is passed back via postback so the tracker can match the conversion to the initial click
  • Conversion: The main user action, such as sale, lead, app install. Affiliates earn commission per each recorded conversion. 
  • Postback URL (callback URL): Server-to-server endpoint that receives information about a conversion event. When a conversion happens, the affiliate network’s server sends a request to this URL with parameters such as click ID and payout.  
  • Tracker: Software that unifies all your campaign data in one place. It usually integrates with both your ad platform and affiliate network to provide a full overview of your performance. 

How Postback Tracking Works (Server-to-Server Explained)

Postback tracking works by sending conversion data directly from one server to the other. 

For example, when a visitor clicks an affiliate link, a unique click ID is generated and recorded by the tracker. When the user converts (either by completing a form or making a purchase etc), the affiliate network’s server sends the conversion details back to the tracker using a postback URL. This server-to-server communication basically ensures that the conversion is linked to the original click

Postback URL Structure and Components

As explained above, a postback URL is the web address that is used to pass conversion data. It typically includes parameters that carry key identifiers and performance data, allowing the tracking platform to attribute conversions correctly. 

Here are the most common parameters passed through the postback URL: 

  • Click ID: The unique identifier that ties conversions to their original click. 
  • Payout: The monetary value of the conversion, which is used to calculate revenue. 
  • Event type: E.g., sign-up, lead, purchase, add to cart, etc. 

These parameters are sent as part of the URL’s query string. Below, we will show an example of a postback URL. 

Typical Postback Flow in Affiliate Campaigns

How Postback Tracking Works

The flow generally starts with a visitor clicking on the affiliate link (usually from an ad on social or native ad platforms). Their unique click ID is generated. This ID is stored in the tracker (along with other metadata), and it will be used to attribute the initial click to the eventual conversion. 

Once the visitor converts, this conversion will be recorded on the affiliate network’s server (i.e., advertiser platform). From their server, the postback URL is triggered to the tracker platform, including parameters such as click ID, payout, event type etc. 

The tracking platform extracts the click ID and other data from this postback request, and it records the conversion in real time

For better results, most affiliates also send these conversions from their tracker to the ad platform, either through conversion API or postback (more on this later).  

Why Postback Tracking Is So Important in Affiliate Marketing

The core benefit of using postback tracking is that it does not rely on browser cookies and privacy limitations, so affiliates can reliably attribute conversions. As explained before, the conversion data is sent directly from the affiliate network to the tracking platform. Attribution also remains reliable when visitors switch devices, preventing any data loss. 

This server-to-server approach is especially important in affiliate campaigns, where accurate attribution determines not only how much an affiliate gets paid but also how you optimize and scale campaigns. With postbacks, every conversion is tied directly to the original click ID, giving you clean, real-time insights into campaign performance rather than estimates or partial data. This helps affiliate marketers identify top-performing ads and traffic sources, and reduce wasted ad spend. 

Another reason postback tracking is essential is that it protects you against future browser privacy changes. With modern privacy regulations and major browsers increasingly limiting third-party cookies, server-side tracking is no longer optional but necessary to ensure full visibility into user behaviour and conversions. 

Postback Tracking vs Pixel vs API (Key Differences Explained)

Quick Comparison 

Feature Postback Tracking Pixel Tracking API Tracking
Tracking Method Server-to-server Client-side Server-to-server integration
Data Accuracy High Moderate to low High to very high
Dependency on Browser No Yes No
Ease of Implementation Moderate to complex (easy with a tracker) Easy Moderate to complex (easy with a tracker)
Fraud Resistance Stronger Weaker Strong
Cross-Device Tracking Excellent Limited Excellent

Pixel Tracking Overview

Unlike postback tracking, pixel tracking is fully dependent on browser cookies. It tracks conversions by loading a script or image (pixel) on the user’s browser after they take certain actions (usually placed in the Thank You page). 

As explained throughout the article, its dependency on browser cookies poses a problem for data accuracy because it can lose conversions due to blocked cookies, JS errors, or page load issues.

It’s a popular tracking method because it’s very simple to set up, but it comes with many limitations. The most important limitation for affiliates is that since the advertiser usually owns the Thank You page, you might not be able to place the pixel at all. 

Conversion API Overview

Conversion API shares more similarities with postback tracking because they are both server-side, and thus independent of browser limitations. 

Conversion API works through two servers directly integrating and communicating with each other. In simple terms, a conversion API acts like a direct link between your backend system and the ad platform’s servers. Most affiliate marketers use Conversion API alongside postback tracking. For example, you use postback tracking to receive conversion events from your affiliate network in your tracker, and then you use the Conversion API to send these conversions directly to your ad platform for better campaign optimization

Setting it up on your own can be technical, which is why most affiliates use a tracking platform with built-in Conversion API integrations, such as ClickFlare. These tracking platforms connect to major ad networks for you, so you can enable server-side tracking with minimal effort and no custom code. 

Pros of Postback Tracking Cons of Postback Tracking
Accurate conversion tracking: Due to it being server-side More technical setup: Compared to pixels, but not if you use a tracker
Bypasses browser restrictions Requires affiliate network support: Network should support postbacks (most do)
Reliable across devices & sessions: If the user switches devices or converts throughout sessions, you won’t lose the conversion Documentation needed: Need to know exactly how the network handles postbacks (most trackers have ready-made templates)
Better fraud security: Harder to breach compared to client-side tracking

How to Use Postback Tracking With ClickFlare

ClickFlare makes working with postbacks very simple for affiliates, so you only need to copy and paste the postback URL without having to worry about the technical setup. 

ClickFlare has more than 150 ready-made tracking templates for top affiliate networks, so you only need to select your network from this list: 

how to use postback tracking with clickflare part 1

Note: If your affiliate network is not on this list, don’t worry. We only need the documentation from your network, and we can create a custom template for you. 

Once you click on one of the options, for example ClickDealer, you will see this screen, already pre-filled in with the required parameters from your network:

how to use postback tracking with clickflare part 2

You can add additional parameters, but in most cases the setup above would work. 

If you scroll below, you will find the postback URL (which is automatically generated by ClickFlare). You simply need to copy it and paste it in your affiliate network. This will ensure that conversions are posted from your network to ClickFlare.

how to use postback tracking with clickflare part 3

Note: Some affiliate networks allow you to set a global postback, which means you only need to set this once and it will be applicable for all your campaigns. If this option is not available, you will need to set this postback for each campaign. 

Best Practices for Postback Tracking Implementation

Before running large-scale tests, we recommend going over the following steps to ensure your postback tracking setup works: 

  • Use unique click IDs: Make sure every click generates a distinct identifier so conversions can be matched precisely back to the original clicks. Unique identifiers are the backbone of accurate server-to-server attribution. 
  • Test before going live: Always run test conversions to verify that your postback URL sends the right data and that your tracker records it correctly. Testing early helps you catch errors before they affect live campaigns. 
  • Monitor in real time: When you launch a new campaign, make sure to keep an eye on all platforms (your affiliate network, tracker, and ad network) to make sure the data matches in all three of them. Once a conversion happens on your affiliate network, it should be sent in real-time to your tracker (for example ClickFlare), and from your tracker to your ad network. 

Real-World Use Cases of Postback Tracking in Affiliate Marketing

Due to the benefits of postback tracking we mentioned before, this method is heavily used in the affiliate marketing space: 

  1. Lead Generation Offers: With these campaigns affiliates get paid for form sign-ups, quote requests, submits etc, so postback tracking is crucial to ensure every lead is attributed back to the traffic source. 
  2. Cost-per-Lead (CPL) Models: Another example where precise attribution is a must-have is CPL offers, where payouts are based on actual leads delivered. With postback tracking, every qualified lead will be properly attributed. 
  3. Cross-Device Funnels: Many users click an affiliate link on their phone, then convert later on desktop. Since traditional cookie-based methods often fail in cross-device paths, postback tracking’s server-to-server flow captures these leads accurately no matter where the conversion takes place.
  4. Pay-Per-Call Tracking: In these types of campaigns, leads are generated by a phone call. Postback tracking ties inbound calls to the original click ID stored on the server. This lets affiliates know which calls were truly driven by which campaigns, which in turn increases payout accuracy and allows for more efficient optimization strategies. 

Postback Tracking FAQs

Q: What is postback tracking?

Postback tracking is a server-to-server (S2S) way of sending conversion data from an affiliate network or advertiser directly to a tracking platform, bypassing browser-dependent methods like cookies or pixels. This makes conversion attribution more accurate and reliable.

Q: How does postback tracking work?

When a user clicks an affiliate link, the system generates a unique identifier (click ID). If the user converts later, the network’s server sends conversion details, including the click ID, back to the tracker through a postback URL. The tracker then matches it to the stored click to log the conversion.

Q: Why should affiliates use postback tracking instead of pixel tracking?

Postback tracking doesn’t rely on browser limitations, so it isn’t affected by ad blockers or privacy restrictions. This means affiliates get cleaner, more reliable conversion data with fewer lost events than with pixel tracking.

Q: What kinds of actions can be tracked with a postback?

Postbacks can record many types of conversions, including lead form submissions, sales, app installs, trial sign-ups, and multi-step funnel events. 

Q: Is postback tracking harder to set up than pixel tracking?

Yes. Because it requires backend configuration and support from the affiliate network, postback tracking can be more technical to implement than a simple browser pixel. However, many affiliates use tracking platforms with ready-made postback integrations. 

Q: Why do affiliates use a tracker for postback tracking?

Affiliates typically use a tracking platform because it collects all campaign data in one place and handles the server-to-server postback process for you. Rather than building your own backend integration, a tracker already has ready-made postback integrations with major affiliate networks and traffic sources, so it makes setup much easier and accurate. 

Conclusion

Postback tracking is widely regarded as the gold standard of tracking in affiliate marketing due to its high accuracy and independence of browser-based tracking

Most affiliate marketers use a tracking tool like ClickFlare to avoid having to set up their own server solution. Instead, they rely on the tracker’s ready-made postback integrations with major affiliate networks. Using a tracker makes postback tracking simple and straightforward to implement. 

You can use postback tracking across all types of affiliate offers, including lead generation, pay-per-call, CPL-models, and cross-device conversions

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